1. Technical Field
The disclosure relates to backlight driving systems, and particularly to a light emitting diode backlight driving system.
2. Description of Related Art
LEDs are arranged in parallel strings in liquid crystal displays (LCDs) driven by a direct current (DC) to DC converter and a multi-channel constant current driver. The multi-channel constant current driver outputs regulating voltage to regulate output voltage of the DC to DC converter to achieve high converting efficiency. However, several values of driving current need to be supplied to the LEDs to achieve different brightness levels. Thus, the regulating voltage of the multi-channel constant current driver varies greatly, which reduces converting efficiency.